Venus Flytraps Don’t Trap And Eat Insects That Serve As Pollinators

Almost everyone saw or at least heard of the carnivorous Venus flytrap plant and it’s iconic snapping jaws. This plant (Dionaea muscipula) continues to surprise us with unexpected mysteries about its life cycle and modus operandi. There is still a lot that scientists don’t know about the biology of these carnivorous plants, but we’ve learned recently about insects that pollinate the rare plants in their native habitat – and discovered that the flytraps “choose” not to trap and feed on these pollinator species!

Dionaea muscipula are in a genus all their own, and are native to a relatively small area, restricted to a rather small (environmentally speaking) 100-mile radius of Wilmington, N.C.

“These findings answer basic questions about the ecology of Venus flytraps, which is important for understanding how to preserve a plant that is native to such a small, threatened ecosystem,” according to Elsa Youngsteadt, a research associate at North Carolina State University and lead author of a paper on the work.

“It also illustrates the fascinating suite of traits that help this plant interact with insects as both pollinators and prey,” she adds. The paper, “Venus Flytrap Rarely Traps Its Pollinators,” is published in the journal American Naturalist.

For this test, researchers had decided to capture insects found on Venus flytrap flowers at several sites during the plant’s five-week flowering season. The researchers identified each insect and checked to see if they were carrying Venus flytrap pollen – and, if they were carrying pollen, how much.

Around 100 types of insects were found on the flowers and only a few of them were both common and pollen carriers. A green sweat bee (Augochlorella gratiosa), a checkered beetle (Trichodes apivorus) and the notch-tipped flower longhorn beetle (Typocerus sinuatus).

The researchers also retrieved prey from more than 200 flytraps at the study sites. The three most important pollinator species – despite being found so often on the flowers – were never found in the traps.

“One potential reason for this is the architecture of the plants themselves,” Youngsteadt says. “Venus flytrap flowers are elevated on stems that stand fairly high above the snap traps of the plant, and we found that 87 percent of the flower-visiting individuals we captured – including all three of the most important species – could fly.

“We also want to learn more about the flytrap’s pollination biology,” says Rebecca Irwin, study co-author and a professor of applied ecology at NC State. “How much and what kind of nectar do they produce? How much pollen do they need to reproduce successfully?